Why didn’t this exist before? Good Guide, a site which rates green products, tabulated political contributions data from 2004-2008, and created an excellent infographic, showing exactly how Democratic or Republican a given company’s donations tended to lean. (Mousing over a company logo yields the detailed data.) The graphic itself isn’t beautiful, but it’s fascinating and useful.

Where it gets really interesting is all the ways you can filter and rank companies–the most interesting one being industry. The results are sometimes surprising, but often confirm what you expected. For example, big content producers (i.e. the entertainment industry) all donate overwhelmingly Democratic. Pinko Hollywood!

Retail, meanwhile, is a bit of a hodgepodge–perhaps reflecting the fact that huge retailers themselves tend to be a pretty mixed representation of the population at large, since they cater to everyone, and have such large workforces. (The graphic is much longer, but I couldn’t grab more, due to the Flash animation. Flash sucks.)

And that brings us to most interesting examples. Tobacco and transportation–two industries with calamitously harmful byproducts (that is, carcinogens and carbon). They tend to lean heavily Republican. These are industries most heavily affected by regulations, from cigarette marketing to emissions targets.

Here’s transportation:

Meanwhile, probably the most heavily educated industry of the lot–technology–tends to lean Democratic. That’s illustrative of a broader, demographic theme, frequently cited by political pundits: The Republican party has been losing the allegiance of highly-educated technocrats–people like lawyers, doctors, and computer engineers. (For example: Polling from the 2008 presidential election showed that Obama had his highest margins among those with graduate degrees.)